Wire spoke automotive wheel

ABSTRACT

A wire spoke, non-suspension type, automotive wheel in which the spokes are operably untensioned prior to vehicle loads being placed upon the wheel. An outer tubeless tire rim with a drop center is mounted to a wheel center which includes a substantially thick and solid felly connected to a concentrically positioned hub. Wire spokes extend radially outward from the hub in circumferential array and have tenons or feet on inner ends thereof which are anchored within recesses at front and rear ends of the hub. Radially outer ends of the spokes are plain terminations welded in the shape of a plug anchor within circumferentially spaced bores in the felly to secure the spokes and permit wheel formations which exhibit the classic beauty and elegance of a suspension wire spoke wheel, combined with durability, strength and ease of construction.

This invention relates to inexpensively produced wire spoke wheels andparticularly to such wheels especially suitable for use withconventional tubeless tires and which are sturdy and durable.

Heretofore, wire spoke automobile wheels which permit the use oftubeless tires have been difficult and costly to make. A typical methodof manufacture involved the projection of wheel spoke nipple endsthrough holes in a rim drop center, which often interfered withmaintaining a reliable and effective air-tight seal. In an effort toovercome this problem, structures have been suggested utilizing spokeends which are connected to a felly mounted concentrically inwardly ofthe rim drop center. This makes a reliable mounting for tubeless tires,but is necessarily complex and expensive. Further, neither arrangementeffectively confronts the predominate problems associated with the useof "suspension" wire spoke wheels; namely, original tension alignment or"tuning" and subsequent slackening or "detuning" of spokes after periodsof use or striking resisting obstacles such as curbs, chuckholes and thelike.

Moreover, the cost of manufacturing suspension wheels is inherentlyquite high because considerable handwork is required during the assemblyand spoke tuning processes. Thus, a typical suspension wire wheel oftencosts over twice as much as a comparable, non-wire spoke, decorativewheel while being less durable.

Within the past few years, certain automotive wheel manufacturers haveattempted to overcome the problems associated with wire suspensionwheels by employing relatively rigid and non-tensioned bars extendingradially between the hub and rim. Though functionally effective, thesegenerally are heavier and do not have the consumer demand of a wirespoke wheel.

The principal objects of the present invention are: to provide a wirespoke wheel for tubeless tires having advantages of wire suspensionwheels without many of the disadvantages; to provide such a wire spokewheel utilizing an effective arrangement for securely connecting spokeinner ends to a tubular hub assembly; to provide such a wheel havingnovel part cooperation by which spoke outer ends are easily and securelyconnected to a felly; to provide such a wheel in which spokesinterconnect a felly and a tubular hub assembly in an operablyuntensioned condition, avoiding tension tuning; to provide a method ofspoke wheel manufacture in which outer ends of the spokes are pluganchored to the felly using novel spoke tip welding procedures; and toprovide a wire spoke wheel which is relatively inexpensive to produce,sturdy and durable in use and adaptable to forms having particularbeauty and consumer demand.

Other objects and advantages of this invention will become apparent fromthe following description taken in connection with the accompanyingdrawings wherein are set forth, by way of illustration and example,certain embodiments of the present invention.

FIG. 1 is a front elevational view of a wire spoke wheel embodying thepresent invention.

FIG. 2 is a rear elevational view of the wheel with portions broken awayto show internal construction.

FIG. 3 is a vertical cross-sectional view through the wheel taken alongline 3--3, FIG. 2.

FIG. 4 is an exploded, perspective view of the wheel hub assembly.

FIG. 5 is a fragmentary front elevational view of the hub.

FIG. 6 is a rear elevational view of the rear of the hub.

FIG. 7 is an exploded fragmentary view of a portion of the hub assemblyand showing aligned recesses for receiving footed spoke hub or innerends.

FIG. 8 is an enlarged, fragmentary view showing paired spoke endreceiving recesses in the hub rear.

FIG. 9 is an enlarged, fragmentary view of paired spoke hub or innerends.

FIG. 10 is an enlarged, fragmentary, cross-sectional view taken alongline 10--10, FIG. 9.

FIG. 11 is an enlarged, fragmentary, cross-sectional view taken alongline 11--11, FIG. 9.

FIG. 12 is an enlarged, fragmentary, cross-sectional view taken alongline 12--12, FIG. 1, showing details of the hub assembly.

FIG. 13 is an enlarged, fragmentary, cross-sectional view taken alongline 13--13, FIG. 4, showing details of a hub rear ring member.

FIG. 14 is an enlarged, fragmentary, cross-sectional view showing theconnection between the ends of the spokes and the felly, taken alongline 14--14, FIG. 2.

FIG. 15 is a greatly enlarged, fragmentary, cross-sectional viewillustrating the insertion of a spoke outer end into a felly borepreparatory to welding for forming a connection therebetween.

FIG. 16 is a greatly enlarged, fragmentary view showing a sectionthrough a felly bore with welding apparatus in place.

FIG. 17 is a greatly enlarged, fragmentary view taken on the line17--17, FIG. 16, showing the path taken by the welding rod tip duringwelding of a spoke outer end.

FIG. 18 is a greatly enlarged, fragmentary, cross-sectional view showinga welded plug connection between a spoke outer end and the felly, thefelly being capped by a tubeless wheel rim.

FIG. 19 is a view similar to FIG. 18 but showing the plug connectionbroken by a severe blow but still retained within the felly.

Referring to the drawings in more detail:

The reference numeral 1 generally indicates a wire spoke wheel embodyingthe present invention. The wheel 1 includes an outer tubeless tire rim2, a felly 3 mounted concentrically inwardly of the rim 2 and a hubassembly 4 positioned concentrically inwardly of the rim 2. Operablyuntensioned wire spokes 5 interconnect the hub assembly 4 and the felly3 in a circumferential array and therewith form a wheel center 6 whichis connected to the tire rim 2.

As best seen in FIG. 3, the tire rim 2 includes front and rear tire beadseats 9 and 10 and front and rear inclined walls 13 and 14 which extendinto a reduced diameter portion or so-called drop center 16. The shapeof the tire rim 2 is conventional to a modern tubeless tire and permitsan air-tight or leak-free seal therewith. A port (not shown) through afront inner wall portion 11 is provided for an inflation valve (notshown).

The felly 3 is mounted concentrically inwardly of the drop center 16and, in this example is formed of a length of solid, rolled, strap steelwelded into a hoop, providing strength and rigidity for the wheelassembly. A plurality of bores 19 extend circumferentially around andradially through the felly 3 at predetermined positions for receivingand anchoring radially outer ends 7 of the wire spokes 5 as describedbelow. The felly 3 has inner and outer annular surfaces 20 and 21 ofwhich the outer surface 21 is conformingly mounted to the drop center16.

As shown in FIG. 14, the bores 19 are aligned in a first row 23 adjacenta rear edge 26 of the felly and a second row 24 adjacent a front edge 25thereof. The rear row 23 is formed of single, spaced bores 19 whereasthe front row 24 is made up of spaced-apart pairs thereof.

The bores 19, FIGS. 15-16, extend through the felly 3 from the innerannular surface 20 to the outer annular surface 21 and include a boreportion 28 of lesser diameter and a co-axial counterbore portion 29 ofgreater diameter which extends inwardly from the outer annular surface21 approximately half of the thickness of the felly 3. The juncturebetween the counterbore portion 29 and the bore portion 28 forms aninterior circular shoulder 30.

The hub assembly 4, FIG. 4, includes a hub piece 33 formed of materialsufficiently strong to resist the applied loads, such as steel, die-castaluminum alloy or the like. The hub piece 33 exhibits front and rearends 34 and 35, an axial bore 36 extending therethrough and front andrear flange sections 38 and 40 to which the inner ends of the spokes 5are connected as described below. To provide a relatively broad face 41,for planar engagement with the surface of the vehicle hub, and toprovide ample space for elongated lug holes 42, the rear flange section40 is of substantially greater radial extent than the front connectingflange section 38. Indented or recessed areas 43 in the flange 40, andsurrounding the lug holes 42, permit emplacement of conventional washers(not shown) with either a centered or an offset bore for universallymounting the wheel 1 to various pattern vehicle hubs.

The exterior surface 44 of the hub piece 33 tapers radially outwardlyand smoothly toward the rear flange 40. Additionally, the hub bore 36includes a series of steps or tapered shoulders 46 which vary the insidediameter as needed for sufficient wall strength with minimum weight. Aninterior shoulder 47, located adjacent the hub front end 34, provides anabutment surface for engagement with a retaining plate 48 having anaxial bore 49 communicating with a fastener, such as a nut 50, affixedto the plate as by welding. A decorative hubcap 52 has a bolt shank orthreaded post 53 mounted on the backside thereof for engagement with thenut 50, to mount the hubcap 52 over the front end 34.

In the illustrated example, the wire spokes 5 are formed of a suitablematerial, such as steel, and include front spokes 55 and rear spokes 57which have respective angled shafts 60 with radially inner ends 58 andouter ends 59, FIG. 4. The inner ends 58 have enlarged tenons or feet 61with outwardly inclined surfaces 62 and a flat bottom or base 63arranged in a circular wedge shape. The front spokes 55 are each singlyarranged and the rear spokes 57 are joined together at adjacent feet 61in conformance with the structure discussed above in connection withFIG. 14. The outwardly inclined upper surfaces 62 merge togetheradjacent the peripheries thereof in a juncture 65, FIGS. 9-11.

As best shown in FIGS. 1 and 2, there are thirty spokes 5 in theexemplary wheel 1 and the front spokes 55 are of greater length than therear spokes 57 in order to reach the felly 3 from an axially forward andgreater radially inward position, FIG. 3. The spoke outer ends 59, notedabove are plain terminations; that is, they have no radially outwardlyextended or expanded portions, but rather, a plain end surface 64, FIG.15, which is preferably chamfered or broken at the rounded edge.

The inner and outer ends 58 and 59 are each terminations of legs orshafts 60 bent so that the respective ends 58 and 59 extendsubstantially radially into the felly 3 and hub 4, although the balanceof the spokes extend at various angles to the radial as shown in FIGS. 1and 3. The front spokes 55 project between the front connecting flange38 and the row 23 of bores 19 adjacent the felly rear edge 26.Conversely, the rear spokes 57 extend from the rear flange 40 to the row24 of paired bores 19 adjacent the felly front edge 25, crossing thefront spokes 55, FIG. 3.

The hub front connecting flange section 38 includes means engaging andanchoring the radially inner ends 58 of the front spokes 55. In theillustrated example, the front connecting flange section 38 receives afront ring member 67 which is telescopically sleeved over thecylindrical shoulder 68 of the hub front end 34. The front ring member67 has inner and outer cylindrical surfaces 69 and 70 and front and rearradial edges or walls 71 and 72. The front edge or wall 71 has aperipheral chamfer or shoulder 74 thereon.

Circumferentially spaced around the front ring member rear edge or wall72 are mortises or recesses 76 for receiving a portion of the spokeinner ends 58, each such mortise or recess having a partial bore portion77 and an inclined foot portion 78 corresponding in dimension to thespoke shaft 60 and the tenon or foot 61. Land portions 79 compriseraised areas between the mortises or recesses 76 and lie adjacent tocorresponding portions in the front shoulder 68, described below, whenthe front ring member 67 is sleeved over the hub front end 34. Aplurality of bores 80, five thereof in the illustrated example, extendthrough the front ring member 67, from the front edge or wall 71 to therear edge or wall 72, and terminate within a land portion 79 for receiptof fasteners, such as Allen head bolts 81, which recess thereinto andurge the front ring member 67 toward a front hub wall 86, FIG. 5.

The front hub wall 86 extends radially outwardly from the cylindricalsurface 68 and has, in coordination with the configuration of the frontring member 67, a plurality of mortises or recesses 88 arrangedcircumferentially therearound which include bore portions 89 andinclined foot portions 90. Land portions 91 between the mortises orrecesses 88 have bores 92 for receipt of the fasteners 81. The frontspoke inner ends 58 are trapped within opposite paired mortises orrecesses 76 and 88 with the spoke shaft 60 held between the boreportions 77 and 89 and the tenon or foot 61 locked within the footportions 78 and 90. It will be appreciated that the spokes 55 arethereby securely anchored to the hub front end 34 and cannot be pulledtherefrom except by a force great enough to fracture or deform thecooperating structure. Conversely, compressive loads on the front spokes55 toward the hub front end 34 are effectively resisted.

An arrangement similar to that of the hub front end 34 is provided atthe hub rear end 35. A rear ring member 95 telescopically mounts over arear cylindrical surface shoulder 96 on the hub 4 and includes spacedmortises or recesses 103 for receiving paired radially inner ends 58 ofthe rear spokes 57. In the illustrated example, the rear ring member 95includes inner and outer cylindrical surfaces 98 and 99 and front andrear radial edges or walls 100 and 101. A plurality of said pairedmortises or recesses 103 are spaced circumferentially around the frontedge or wall 100 and have bore portions 104 and foot portions 105 forrespective receipt of the spoke shaft 60 and the tenon or foot 61. Therear shoulder 96 extends to a radial rear edge or face 109 havingcoordinatingly positioned and aligned paired mortises or recesses 111with bore portions 112 and foot portions 113. Lands 114 separate andspace each pair of mortises or recesses 111 and relatively smaller arealands 115 separate the individual recesses of the pairs.

A plurality of spaced bores 117, numbering ten thereof in theillustrated example, extend through the rear ring member 95 from thefront edge or wall 100 to the rear edge or wall 101 for receipt offasteners such as recessed Allen head bolts 118 which further engagewithin bores 119 in the lands 114 of the rear face 109.

Like the connecting means of the front ring member 67, the inner ends 58of the paired rear spokes 57 are received within the rear edge or facemortises or recesses 111 and, when the rear ring member 95 is sleevedover the outer surface 96, the rear ring member mortises or recesses 103fit around the joined spoke inner ends 58. Concurrently, the oppositelands 114 and 115 are positioned adjacent their aligned counterpartlands and the rear spoke ends 58 are thereby securely anchored ortrapped within the hub rear end 35.

In the manufacture of the wire spoke wheel 1, the center 6 is firstassembled as described below and then mounted within the tubeless tirerim 2. To assemble the wheel center 6, the hub piece 33 is centeredwithin the felly 3 by the use of a mounting jig (not shown). The frontand rear spokes 55 and 57 are connected at their inner ends 58 to thehub piece 33 and the spoke outer ends 59 are inserted into the fellybores 19 in the resepective rows 23 and 24.

It is preferred that the dimensions of the receiving recesses providesnug engagement with the spoke shafts 60 when the latter are fittedtherein. Further, it is preferred that there be suitable clearances,e.g., 0.003" to 0.005" between the various facing surfaces of the rings95 and 67 and the hub pieces 33 to permit application of a bondingsubstance or agent 121, such as a low viscosity epoxy or the like,therebetween. In addition to improving the mechanical connections, thishelps anchor and prevent unwanted play in the spokes 5. Further, afterthe fasteners 81 and 118 are inserted and tightened, the bonding agent121 is preferably applied to fill in recessed bolt cavities to securethe fasteners 81 and 118 against rotation and prevent tampering afterassembly.

The outer ends 59 of the spokes 5 extend radially approximately halfwaythrough the felly 3 to a position approximately even with the interiorshoulder 30 of the bore 19, FIG. 15. The spoke outer ends 59 are thenanchored within the bore 19 by an electric current welding processutilizing a rosette-forming bead welding device 125. The welding device125 includes a hollow casing feeder 126 from which is fed a welding wire128 of mild steel or the like. The welding device 125 is part of alarger apparatus (not shown) which causes the device 125 to rotativelywobble whereby the end of the wire 128 traverses a circular path (FIG.17) as it continuously extends into the counterbore portion 29 of thebore 19. In the illustrated example, the welding wire 128 isapproximately of 0.035" diameter and is fed from the tip 127 of thewelding device 125 at a rate of approximately five inches per second.Additionally, a circular channel 130 which rings the welding wire 128,transmits therealong a gas mixture, such as 95% argon and 5% carbondioxide, which acts as an inert shield around the welding wire 128 toavoid contamination of the weld.

In forming the weld, the welding wire 128 is inserted into thecounterbore portion 29 and then moved to form a "bead" type deposit inthe noted rotative-wobble pattern to produce a "rosette" or coiled,circular, bead weld formation 129 atop the spoke outer end 59. Theformation 129 is fused both to the spoke top surface 64 and the wall ofthe counterbore portion 29 and roughly constitutes a plug whichlaterally fills the cavity and blends with adjacent surfaces at 133, 134and 135, FIG. 18. Accordingly, the fused or blended portions 133, 134and 135 extend substantially into the material of the felly 3 and spokeouter end 59 and securely anchor the spoke within the felly.

After assembly, the wheel center 6 is mounted within the tire rim 2. Thediameter of the felly 3 is preferably slightly oversize relative to theinterior of the tire rim 2 to provide a tight fit for pressing the wheelcenter 6 into the tire rim 2. Using a truing apparatus, the wheel center6 is adjusted for correct positioning within the tire rim 2 and testedfor both lateral and radial run-out. The felly 3 is then welded alongthe outer periphery of rear edge 26 to the interior of the drop center16. The resultant weld beads 132 may be relatively short segments, asillustrated, or may be a continuous weld. The wheel is cleaned andpreferably chrome plated and polished to increase corrosion resistanceand provide a pleasing appearance.

The hub cap 52 is mounted next to the front connecting flange section38, and centered on the ring member shoulder 74, in order to keep outroad dirt and grime and may be pleasingly decorated with, for example,the wheel manufacturer's mark or emblems designating the maker of theautomobile.

It should be appreciated that, in the event of a substantial collisionwith a resisting object, such as pothole wall, curb, or the like, whichproduces strain loads beyond the elastic limit of the wheel material, afracture or break must result. However, due to the above notedconstruction, such a fracture or break in the spoke-felly engagementarea is not likely to produce the dangerous situation which exists whenthe spokes and felly separate. FIG. 18 shows the normal completedspoke-felly connection, described above. FIG. 19 somewhat schematically,illustrates the results of a severe blow where the radially outwardforce on a spoke 5 has been great enough to cause a material failure.The weld formation 129, or plug, has torn away from the felly base alongslip faults 137 and jammed into the rim drop center 16, where itproduced a deformation in the form of a bulge 142. In so doing, the plugtop 141 has partially disintegrated adjacent felly material at 140creating trapped debris 139. The extent of plug displacement isindicated by the space which may be created below the plug surface 134at 138, FIG. 19. Although a structural failure has occurred, and thewheel is probably no longer sufficiently concentric for long term use,the damaged wheel is not likely to be dangerous for short term use sincesubsequent forces tending to pull the spoke from the felly are resistedby the engagement of the plug with the remnants of the interior boreshoulder 30.

It is to be understood that while one form of this invention has beenillustrated and described, it is not to be limited to the specific formor arrangement of parts herein described and shown, except insofar assuch limitations are included in the following claims.

What is claimed and desired to secure by Letters Patent is:
 1. A wire spoke automotive wheel comprising:(a) a rim adapted for receiving a tire thereon; (b) a felly positioned concentrically inwardly of and mounted to said rim and having a plurality of spaced bores extending circumferentially therearound; (c) a hub positioned concentrically inwardly of said felly; (d) a plurality of operably untensioned wire spokes interconnecting said hub and said felly; (e) said spokes having radially inner ends anchored to said hub and radially outer ends; (f) a weld formation anchoring said respective outer ends within said respective felly bores, (g) said hub including front and rear ends each having an axially inwardly extending cylindrical surface and a radial face with a plurality of circumferentially spaced recesses in said face; and (h) a ring member for said front and rear ends and having a radial face with a plurality of circumferentially spaced recesses therein commensurately shaped and located relative to said respective hub face recesses; (i) said front and rear ring members being telescoped over said respective cylindrical surfaces and positioned adjacent said respective hub radial face with said ring member recesses aligned with said hub recesses, (j) said spoke inner ends being retained in said respective recesses, (k) said hub rear end including a radially outwardly extended flange having said cylindrical surface and radial face thereon.
 2. In a spoked automotive wheel wherein spokes extend into bores, the improvement comprising the combination of:(a) an annular spoke receiving member having an outer surface and spaced bores extending circumferentially therearound, (b) a plurality of metallic wheel spokes respectively having ends with an end surface extending at least a substantial distance thereacross, said spoke ends being inserted within said bores a distance substantially less than the axial length of said bores, creating open, weld wire receiving cavities having a depth extending from said outer surface to said end surface, said cavities respectively being located adjacent and outwardly of said spoke end surfaces and bounded by said end surfaces and a portion of the inner surface of said bores extending outwardly thereof, and (c) metallic wire bead weld formations contained within said cavities and fusedly joined respectively to said spoke end surfaces and to said bore inner surface portions, (d) said weld formations roughly constituting weld metal plugs which substantially laterally fill said cavities and blend with said end surfaces and said bore inner surface portions, thereby securely anchoring said spoke ends at a position partially within said bores against relative movement within said bores between said spokes and spoke receiving member due to automotive vehicle induced forces acting on said spokes.
 3. The wire spoke automotive wheel as set forth in claim 2 wherein:(a) said spoke receiving member is a felly, and (b) said bores include an inner bore portion receiving the outer end of said spoke and an outer bore portion of greater diameter than said inner bore portion and located radially outwardly of said inner bore portion.
 4. The wire spoke automotive wheel as set forth in claim 3 wherein:(a) said weld formation is located primarily in said outer bore portion and is of greater diameter than said inner bore portion.
 5. The wire spoke automotive wheel set forth in claim 3 wherein:(a) an interior shoulder is formed at the juncture of said inner and outer bore portions; and said weld formation is fused to said shoulder.
 6. The wire spoke automotive wheel as set forth in claim 2 wherein:(a) said weld formation is of greater diameter than said spoke outer end.
 7. The wire spoke automotive wheel as set forth in claim 6 wherein:(a) said weld formation substantially fills said outer bore portion.
 8. The wire spoke automotive wheel as set forth in claim 2 including:(a) a rim, (b) said weld formation being capped by said rim whereby said rim tends to block movement of said spoke end further into said bore.
 9. In a spoked automotive wheel wherein spokes extend into bores, the improvement comprising the combination of:(a) an annular spoke receiving member with spaced bores extending circumferentially therearound, (b) a plurality of metallic wheel spokes respectively having ends inserted only partially within said bores, creating open receiving cavities adjacent said spoke ends which are bounded by the end surface of said spoke ends and a portion of the inner surface of said bores, (c) metallic weld formations contained within said cavities and fusedly joined respectively to said spoke ends and to said spoke receiving member, (d) said weld formations roughly constituting plugs which laterally fill said cavities and blend with said end surface of said spoke ends and said portion of the inner surface of said bores, thereby securely anchoring said spoke ends within said bores against relative movement within said bores between said spokes and spoke receiving member due to automotive vehicle induced forces acting on said spokes, (e) said spoke receiving member being a felly, (f) said bores include an inner bore portion receiving the outer end of said spoke and an outer bore portion of greater diameter than said inner bore portion and located radially outwardly of said inner bore portion, and (g) an interior shoulder formed at the juncture of said inner and outer bore portions, (h) said spoke outer end terminating within said felly bore approximately at said interior shoulder.
 10. In a spoked automotive wheel wherein spokes extend into bores, the improvement comprising the combination of:(a) an annular spoke receiving member with spaced bores extending circumferentially therearound, (b) a plurality of metallic wheel spokes respectively having ends inserted only partially within said bores, creating open receiving cavities adjacent said spoke ends which are bounded by the end surface of said spoke ends and a portion of the inner surface of said bores, (c) metallic weld formations contained within said cavities and fusedly joined respectively to said spoke ends and to said spoke receiving member, (d) said weld formations roughly constituting plugs which laterally fill said cavities and blend with said end surface of said spoke ends and said portion of the inner surface of said bores, thereby securely anchoring said spoke ends within said bores against relative movement within said bores between said spokes and spoke receiving member due to automotive vehicle induced forces acting on said spokes, (e) a hub within said annular spoke receiving member, (f) said hub including front and rear ends each having an axially inwardly extending cylindrical surface and a radial face with a plurality of circumferentially spaced recesses in said face, and (g) a ring member for said front and rear ends and a radial face with a plurality of circumferentially spaced recesses therein commensurately shaped and located relative to said respective hub face recesses, (h) said front and rear ring members being telescoped over said respective cylindrical surfaces and positioned adjacent said respective hub radial face with said ring member recesses aligned with said hub recesses, (i) said spoke inner ends being retained in said respective recesses.
 11. The wire spoke automotive wheel set forth in claim 10 wherein:(a) said ring member recesses and said hub recesses have respective coordinating mortise portions; and (b) said spoke inner ends have outwardly extended tenon feet respectively received within said mortise portions.
 12. The wire spoke automotive wheel as set forth in claim 10 including:(a) adhesive between at least one of said ring members and said hub.
 13. The wire spoke automotive wheel as set forth in claim 12 wherein:(a) said adhesive is an epoxy resin. 